Foldable rack

ABSTRACT

A foldable rack includes first and second frame-halves each including at least two horizontal plates, and two upright rods connected pivotally and respectively to front and rear sides of each horizontal plate. Two guide rods are disposed respectively between the upright rods of the frame-halves. Two slide pieces are sleeved slidably and respectively on the guide rods between top and bottom sections thereof, and respectively have a protrusion. Two locking units are disposed respectively on the guide rods between the top and bottom sections thereof. Each locking unit includes a locking element to engage or disengage the protrusion of a respective slide piece so as to prevent or unlock relative sliding movement between one of the slide pieces and a respective guide rod, so that the upright rods of the first and second frame-halves are moved to an unfolded or folded state.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority of Taiwanese Application No. 098224756, filed on Dec. 30, 2009.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a rack, more particularly to a foldable rack.

2. Description of the Related Art

Referring to FIG. 1, a foldable rack, as disclosed in Taiwanese Publication No. M302941, includes two spaced-apart U-shaped main rods 1, a link unit 2, two locking units 3, and two horizontal plate units 4. The link unit 2 includes a U-shaped connecting rod 201 disposed between the main rods 1, two slide pieces 202 sleeved respectively and slidably on two opposite arms of the U-shaped connecting rod 201, and two pairs of link rods 203. Each link rod 203 is connected pivotally between one of the slide pieces 202 and one of the arms of a corresponding main rod 1. The locking units 3 are fixed respectively to top ends of the arms of the U-shaped connecting rod 201. When the main rods 1 are spaced apart from each other at a largest distance, that is, when the main rods 1 are in an unfolded state, the locking units 3 are engaged to the respective slide pieces 202. When the locking units 3 are operated so as to disengage from the respective slide pieces 202, the arms of the U-shaped connecting rod 201 can then be moved upwardly relative to the respective slide pieces 202 to thereby move the main rods 1 close to each other to a folded state.

Although the aforesaid foldable rack can achieve its intended purpose, because the locking units 3 are fixed respectively to the top ends of the arms of the U-shaped connecting rod 201, it is difficult to add more horizontal plate units 4 to the conventional foldable rack so as to increase the height and storage space thereof.

SUMMARY OF THE INVENTION

Therefore, the object of the present invention is to provide a foldable rack that is capable of overcoming the aforementioned drawbacks of the prior art.

According to this invention, a foldable rack comprises first and second frame-halves, two guide rods, two slide pieces, two first link rods, two second link rods, and two locking units. The first frame-half includes at least two horizontal plates, and two spaced-apart upright rods each having top and bottom sections. Each horizontal plate has inner and outer sides, and front and rear sides connected between the inner and outer sides. The upright rods are connected pivotally and respectively to the front and rear sides of each horizontal plate proximate to the outer side thereof. The second frame-half is opposite to the first frame-half, and includes at least two horizontal plates, and two spaced-apart upright rods each having top and bottom sections. Each of the horizontal plates of the second frame-half has inner and outer sides, and front and rear sides connected between the inner and outer sides of a corresponding horizontal plate of the second frame-half. The upright rods of the second frame-half are connected pivotally and respectively to the front and rear sides of each horizontal plate of the second frame-half proximate to the outer side thereof. Each guide rod is disposed between one of the upright rods of the first frame-half and a respective upright rod of the second frame-half. Each guide rod has top and bottom sections. The front side of each horizontal plate of the first frame-half and the front side of each horizontal plate of the second frame-half are connected pivotally to one of the guide rods proximate to the inner sides thereof. The rear side of each horizontal plate of the first frame-half and the rear side of each horizontal plate of the second frame-half are connected pivotally to the other one of the guide rods proximate to the inner sides thereof. Each slide piece is sleeved slidably on a respective one of the guide rods between the top and bottom sections thereof. Each slide piece has a protrusion projecting therefrom. Each first link rod is connected pivotally to and disposed between one of the slide pieces and the bottom section of one of the upright rods of the first frame-half. Each second link rod is connected pivotally to and disposed between one of the slide pieces and the bottom section of one of the upright rods of the second frame-half. The locking units are disposed respectively on the guide rods between the top and bottom sections thereof. Each locking unit includes a locking element to engage the protrusion of a respective slide piece so as to prevent relative sliding movement between one of the slide pieces and a respective guide rod, so that the upright rods of the first and second frame-halves are moved to an unfolded state. The locking element of each locking unit is disengaged from the protrusion of the respective slide piece so as to unlock relative sliding movement between the one of the slide pieces and the respective guide rod, so that the upright rods of the first and second frame-halves are moved to a folded state.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment of the invention, with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a foldable rack disclosed in Taiwanese Publication No. M302941;

FIG. 2 is a perspective view of a foldable rack according to the preferred embodiment of this invention in an unfolded state;

FIG. 3 is a schematic side view of the preferred embodiment;

FIG. 4 is a sectional view of the preferred embodiment taken along line IV-IV of FIG. 3;

FIG. 5 is a view similar to FIG. 4, but illustrating a locking element being disengaged from a protrusion of a slide piece; and

FIG. 6 is a schematic view of the preferred embodiment in a folded state.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 2 to 6, a foldable rack according to the preferred embodiment of the present invention is shown to comprise a first frame-half 10, a second frame-half 20, a link unit 30, and two locking units 40.

The first and second frame-halves 10, 20 are opposite to each other. Each of the first and second frame-halves 10, 20 includes five spaced-apart horizontal plates 12, 22, and two spaced-apart upright rods 11, 21 (only one upright rod 11 is visible in FIG. 2). The horizontal plates 12, 22 of each of the first and second frame-halves 10, 20 are disposed equally spaced apart from each other between top and bottom sections 112, 212, 111, 211 of the upright rods 11. Each horizontal plate 12, 22 has an inner side 122, 222, an outer side 121, 221, a front side 123, 223 connected between front ends of the inner and outer sides 122, 222, 121, 221 and a rear side 124, 224 connected between rear ends of the inner and outer sides 122, 222, 121, 221. The upright rods 11, 21 of each of the first and second frame-halves 10, 20 are connected pivotally to the front and rear sides 123, 223, 124, 224 of the horizontal plates 12, 22 proximate to the outer sides 121, 221 thereof.

The link unit 30 has two guide rods 31, two slide pieces 32, two first link rods 33, and two second link rods 34. Each guide rod 31 is disposed between one of the upright rods 11 of the first frame-half 10 and a respective upright rod 21 of the second frame-half 20, and has a top section 312, a bottom section 311, and five pivot pins 316 spaced apart from each other along the length thereof. The front side 123 of each horizontal plate 12 of the first frame-half 10 and the front side 223 of each horizontal plate 22 of the second frame-half 20 are connected pivotally to one of the guide rods 31 proximate to the inner sides 122, 222 thereof by using a corresponding pivot pin 316. The rear side 124 of each horizontal plate 12 of the first frame-half 10 and the rear side 224 of each horizontal plate 22 of the second frame-half 20 are connected pivotally to the other one of the guide rods 31 proximate to the inner sides 122, 222 thereof by using a corresponding pivot pin 316.

Each slide piece 32 is sleeved slidably on a respective guide rod 31 between the top and bottom sections 312, 311 thereof, and has a protrusion 321 projecting therefrom. Each first link rod 33 is connected pivotally to and is disposed between one of the slide pieces 32 and the bottom section 111 of one of the upright rods 11 of the first frame-half 10. Each second link rod 34 is connected pivotally to and is disposed between one of the slide pieces 32 and the bottom section 211 of one of the upright rods 21 of the second frame-half 20.

A positioning element 314 (see FIG. 4) is fixed around each guide rod 31 between the top and bottom sections 312, 311 thereof through the pivot pin 316 that connects pivotally the front sides 123, 223 of middle ones of the horizontal plates 12, 22 of the first and second frame-halves 10, 20 to the corresponding guide rod 31, and has a rectangular head part 314′. A decorative piece 315 is fixed to a top end of the top section 312 of each guide rod 31.

With reference to FIG. 4, each locking unit 40 includes a locking plate 41 and a biasing element 42. The locking plate 41 has a fulcrummed portion 411 connected pivotally to the positioning element 314, a locking element 412 provided on a bottom end thereof to engage releasably the protrusion 321 of a respective slide piece 32, and a trigger portion 413 opposite to the locking element 412 and disposed below the head part 314′. The biasing element 42 is disposed between the trigger portion 413 and the positioning element 314 so as to bias the trigger portion 413 away from the positioning element 314, so that the locking element 412 and the protrusion 321 are inter-engaged.

With reference to FIGS. 2 and 3, when the foldable rack of the present invention is in an unfolded state, the upright rods 11, 21 of the first and second frame-halves 10, 20 are disposed farthest away from each other, and the horizontal plates 12 of the first frame-half 10 are flush with the respective horizontal plates 22 of the second frame-half 20, and cooperate with the same to form a plurality of shelves for holding objects (not shown). With reference to FIG. 4, the trigger portion 413 is moved away from the positioning element 314 by the biasing action of the biasing element 42, and the locking element 412 is engaged to the protrusion 321 of the respective slide piece 32 so as to prevent relative sliding movement between the slide piece 32 and the guide rod 31. The slide piece 32 abuts against a bottom end of the positioning element 314, and is positioned thereat. Alignment of the horizontal plates 12 of the first frame-half 10 with the horizontal plates 22 of the second frame-half 20 is thus ensured.

With reference to FIG. 5, when the trigger portion 413 is operated so that the trigger portion 413 is moved close to the positioning element 314, the locking element 412 is moved away from the protrusion 321 so as to disengage from the same, thereby unlocking relative sliding movement between the slide piece 32 and the guide rod 31. At this time, the locking plate 41 can be pushed upwardly so as to move therealong the guide rod 31 relative to the slide piece 32. As the guide rod 31 moves upwardly relative to the slide piece 32, the upright rods 11, 21 of the first and second frame-halves 10, 20 move downwardly close toward each other, and the horizontal plates 12, 22 of the first and second frame-halves 10, 20 pivot downwardly relative to the guide rods 31 toward each other, thereby shifting the foldable rack of the present invention from the unfolded state shown in FIG. 2 to a folded state shown in FIG. 6.

It is worth mentioning that, with reference to FIG. 6, when the foldable rack of the present invention is folded, each upright rod 11 of the first frame-half 10 and the respective upright rod 21 of the second frame-half 20 abut oppositely against the head part 314′ of the positioning element 314, so that the upright rods 11, 21 are spaced apart from each other at a small distance. Hence, the foldable rack of the present invention, after being folded, is stable, and has a small volume to facilitate storage, packing, and transport thereof.

Therefore, the foldable rack of the present invention not only has a plurality of the horizontal plates 12, 22, but also can be folded and unfolded as desired. Further, by installing the locking unit 40 to the guide rod 31 between the top and bottom sections 312, 311 thereof, the locking unit 40 can be operated easily so as to fold and unfold the foldable rack of the present invention.

While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretations and equivalent arrangements. 

1. A foldable rack, comprising: a first frame-half including at least two horizontal plates, and two spaced-apart upright rods each having a top section and a bottom section, each of said horizontal plates having inner and outer sides, and front and rear sides connected between said inner and outer sides, said upright rods being connected pivotally and respectively to said front and rear sides of each of said horizontal plates proximate to said outer side thereof; a second frame-half opposite to said first frame-half, and including at least two horizontal plates, and two spaced-apart upright rods each having a top section and a bottom section, each of said horizontal plates of said second frame-half having inner and outer sides, and front and rear sides connected between said inner and outer sides of a corresponding one of said horizontal plates of said second frame-half, said upright rods of said second frame-half being connected pivotally and respectively to said front and rear sides of each of said horizontal plates of said second frame-half proximate to said outer side thereof; two guide rods each disposed between one of said upright rods of said first frame-half and a respective said upright rod of said second frame-half, each of said guide rods having a bottom section and a top section; said front side of each of said horizontal plates of said first frame-half and said front side of each of said horizontal plates of said second frame-half being connected pivotally to one of said guide rods proximate to said inner sides thereof; said rear side of each of said horizontal plates of said first frame-half and said rear side of each of said horizontal plates of said second frame-half being connected pivotally to the other one of said guide rods proximate to said inner sides thereof; two slide pieces each sleeved slidably on a respective one of said guide rods between said top and bottom sections thereof, each of said slide pieces having a protrusion projecting therefrom; two first link rods each connected pivotally to and disposed between one of said slide pieces and said bottom section of one of said upright rods of said first frame-half; two second link rods each connected pivotally to and disposed between one of said slide pieces and said bottom section of one of said upright rods of said second frame-half; and two locking units disposed respectively on said guide rods between said top and bottom sections thereof, each of said locking units including a locking element to engage said protrusion of a respective said slide piece so as to prevent relative sliding movement between one of said slide pieces and a respective said guide rod, so that said upright rods of said first and second frame-halves are moved to an unfolded state, said locking element of each of said locking units being disengaged from said protrusion of the respective said slide piece so as to unlock relative sliding movement between one of said slide pieces and the respective said guide rod, so that said upright rods of said first and second frame-halves are moved to a folded state.
 2. The foldable rack of claim 1, further comprising a positioning element fixed around each of said guide rods between said top and bottom sections thereof, each of said locking units further including a locking plate connected pivotally to said positioning element, and a biasing element, said locking plate having said locking element provided on one end thereof, and a trigger portion opposite to said locking element, said biasing element being disposed between said positioning element and said trigger portion to bias said trigger portion away from said positioning element. 